Sedimentary and Petrologic Analysis of the Mississippian Price Formation at Sherwood Lake, West Virginia
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Graduate Theses, Dissertations, and Problem Reports 2002 Sedimentary and petrologic analysis of the Mississippian Price Formation at Sherwood Lake, West Virginia Laura Ruth Sheehan West Virginia University Follow this and additional works at: https://researchrepository.wvu.edu/etd Recommended Citation Sheehan, Laura Ruth, "Sedimentary and petrologic analysis of the Mississippian Price Formation at Sherwood Lake, West Virginia" (2002). Graduate Theses, Dissertations, and Problem Reports. 1535. https://researchrepository.wvu.edu/etd/1535 This Thesis is protected by copyright and/or related rights. It has been brought to you by the The Research Repository @ WVU with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you must obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in WVU Graduate Theses, Dissertations, and Problem Reports collection by an authorized administrator of The Research Repository @ WVU. For more information, please contact [email protected]. SEDIMENTARY AND PETROLOGIC ANALYSIS OF THE MISSISSIPPIAN PRICE FORMATION AT SHERWOOD LAKE, WEST VIRGINIA Laura R. Sheehan Thesis Submitted to The College of Arts and Sciences at West Virginia University In partial fulfillment of the requirements for the degree of Master of Science in Geology Committee members: Dr. Richard Smosna, Ph.D. Dr. Thomas Kammer, Ph.D. Dr. Helen Lang, Ph.D. Department of Geology and Geography Morgantown, West Virginia 2002 Keywords: Price Formation, Mississippian, Petrology, Sedimentology Depositional facies determinations of the upper member of the Price Formation were made based on detailed descriptions of the six outcrops exposed along Sherwood Lake Road, Greenbrier County, West Virginia. Units were placed into one of seven facies: fluvial, distributary channels, crevasse-splays, swamp, beach-bar, lagoon, and interdistributary bay. Sandstone units of the respective facies were then petrographically analyzed. Petrographic analysis indicates that there are distinct differences in mineralogies among the facies, particularly in the type of lithic grains present within the sandstones. High percentages of schist and phyllite rock fragments within the upper-delta-plain facies indicate that the parent material for the Price in southern West Virginia was dominantly metamorphic. Percentages of rock fragments change sytematically down the regional slope; upper-delta-plain facies have high percentages of metamorphic rock fragments (schist and phyllite) and lower-delta-plain facies have abundant sedimentary rock fragments (shale). The change in rock fragments down the paleo slope can be attributed to 1) increased mechanical degradation of metamorphic rock fragments with greater distance from the source area and 2) the introduction of sedimentary rocks fragments that were locally derived from within the mud-rich beds, typically more common in the lower portions of the deltaic system. iii ACKNOWLEDGMENTS Written endeavors such as this are rarely the work of one person. I wish to acknowledge the assistance that many of my colleagues and professors have given to me, and extend particular thanks to certain individuals. My advisor Dr. Richard Smosna was not only an invaluable source of information, ideas and critical comments, but he was also an enthusiastic supporter of this particular project. The time and energy which he put into this mission is much appreciated, and for all of this I owe him many thanks. Dr. Thomas Kammer generously gave his time to explain the stratigraphy and nomenclature of the Price in great detail, and also lended his guidance in field techniques and tactics. I would also like to thank Dr. Helen Lang for her time and insightful comments. Her help with the petrology portion of this project has been obliging. Special gratitude must also be extended to Phillips Petroleum Company who kindly funded all costs for the preparation of thin sections, and to Dr. Smosna who was the bridging liaison for the financial contribution, an added bonus which was greatly appreciated by the author. Finally, I would like to thank my family and friends who have supported me through this long and arduous journey. My parents have instilled me with independence and determination, and guided me with love and understanding. For this I owe them more than words can tell. My siblings and friends have been my staunchest supporters, and I only wish I can help them as much as they’ve helped me. iv TABLE OF CONTENTS PAGE ABSTRACT ii ACKNOWLEDGMENTS iii LIST OF FIGURES vi INTRODUCTION 1 Geological Setting 1 Area of Study 11 Purpose of Study 11 Methodology 13 DEPOSITIONAL ENVIRONMENTS 15 Delta Plain 15 Meandering Channel Facies 28 Distributary Channel Facies 38 Crevasse-Splay Facies 42 Interdistributary Swamp 45 Interdistributary Bay Facies 47 Delta Front 51 Beach-Bar 53 Lagoon 58 SEDIMENTARY PETROLOGY 64 Petrography 64 Quartz 64 Feldspars 69 Lithic Fragments 69 Micas 71 Iron Minerals 74 Heavy Minerals 76 Calcite and Fossils 76 Matrix and Cement 77 Petrologic Interpretation 79 Meandering Channel Facies 80 Distributary Channel Facies 82 Crevasse-Splay Facies 87 Beach-Bar Facies 87 Lagoon Facies 91 Interdistributary Bay Facies 91 Summary of Petrologic Analysis 94 v CONCLUSIONS 103 REFERENCES 106 APPENDIX A 110 Measured Sections at Sherwood Lake APPENDIX B 121 Point-Count Data vi LIST OF FIGURES Figure 1 Isopach map of the Price Formation in West Virginia. 5 Figure 2 Stratigraphic cross section from Bluefield to Sidling Hill. 6 Figure 3 Chronostratigraphic chart for the Price Formation. 9 Figure 4 Location map of Greenbrier County 12 Figure 5 Location map of Sherwood Lake outcrops 12 Figure 6 Stratigraphic Symbols used in stratigraphic columns. 16 Figure 7 Outcrop 1 stratigraphic column 17 Figure 8 Outcrop 2 stratigraphic column 18 Figure 9 Outcrop 3 stratigraphic column 19 Figure 10A Outcrop 4 stratigraphic column 20 Figure 10B Continuation of outcrop 4 stratigraphic column. 21 Figure 10C Continuation of outcrop 4 stratigraphic column. 22 Figure 11A Outcrop 5 stratigraphic column 23 Figure 11B Continuation of outcrop 5 stratigraphic column. 24 Figure 12 Outcrop 6 stratigraphic column 25 Figure 13 Composite stratigraphic column for all 6 outcrops 26 Figure 14 3-D model of depositional environments present at Sherwood Lake. 27 vii Figure 15 Stratigraphic column typically found in lower- delta-plain deposits. 29 Figure 16 Photographs of outcrop 6. 30 Figure 17 Photographs of large-scale cross-beds present in fluvial sandstones. 31 Figure 18 Photographs of fluvial sandstones displaying scour-and-fill structure. 32 Figure 19 Close-up photograph of scour-and-fill structure present at outcrop 6. 33 Figure 20 Typical fining-upward sequence of meandering stream deposits. 35 Figure 21a. Lateral accretion cross-bedding in small fluvial channel bodies. 37 Figure 21b. Model for fluvial deposition yielding mult- story sandbodies. 37 Figure 22 Photographs of upper distributary channels present at outcrop 5. 39 Figure 23 Typical sequence present in distributary channel facies. 41 Figure 24 Photographs of large-scale trough cross- beds present in upper distributary channel facies. 43 Figure 25 Photographs of large-scale planar cross- beds present in the lower-distributary channel facies. 43 Figure 26 Photographs of the crevasse-splay faices 44 Figure 27 Examples of crevasse-splay deposits found at Sherwood Lake 46 Figure 28 Photographs of the coal deposits present at outcrop 5. 48 Figure 29 Photographs of the interdistributary bay facies. 49 viii Figure 30 Typical stratigraphic column of bay-fill succession. 52 Figure 31 Photographs of Unit 24- Transgressive lag deposit. 54 Figure 32 Stratigraphic cross-section of Price Formation from Bluefield to Crystal Springs, PA. 55 Figure 33 Typical shoreline sequence. 57 Figure 34 Photographs of Unit 26- Shoreface deposits. 59 Figure 35 Photograph of Unit 27- foreshore deposits. 60 Figure 36 Photographs of lagoonal deposits 61 Figure 37 Stratigraphic column for the lagoonal facies 63 Figure 38 QFL diagram for all 57 thin-section samples 65 Figure 39 SPS diagram for all 57 thin-section samples 65 Figure 40 Petrographic photo plate: A. and B. Quartz-rich sample, C. and D. sublitharenite. 66 Figure 41 Petrographic photo plate: A. and B. Lithic-rich sample, C. Undulose quartz, D. Polycrystalline quartz. 67 Figure 42 Petrographic photo plate: A. Chert, B. Plagioclase feldspar, C. Microcline feldspar. 70 Figure 43 Petrographic photo plate: A. and B. Phyllite grain, C. and D. abundant rock fragments with phyllite dominant. 72 Figure 44 Petrographic photo plate: A. and B. Schist rock fragment, C. and D. deformed muscovite grain. 73 Figure 45 Petrographic photo plate: A. abundant hematite, B. siderite, C. Gastropod and calcite crystals D. matrix 75 ix Figure 46 Petrographic photo plate: A. and B. Pseudo- matrix. 78 Figure 47 QFL diagram for fluvial facies. 81 Figure 48 SPS diagram for fluvial facies. 81 Figure 49 QFL diagram for upper distributary channel facies. 83 Figure 50 SPS diagram for upper distributary channel facies. 83 Figure 51 QFL diagram for lower distributary channel facies. 86 Figure 52 SPS diagram for lower distributary channel facies. 86 Figure 53 QFL diagram for crevasse-splay facies 88 Figure 54 SPS diagram for crevasse-splay facies 88 Figure 55 QFL diagram for beach-bar facies 89 Figure 56 SPS diagram for beach-bar facies 89 Figure 57 QFL diagram for lagoon facies 92 Figure 58 SPS diagram for lagoon facies 92 Figure 59 QFL diagram for interdistributary bay facies. 93 Figure 60 SPS diagram for interdistributary bay facies. 93 Figure 61 SPS diagram for mean of all facies 96 Figure 62 Ratio of total metamorphic rock fragments relative to total quartz for all facies 98 Figure 63 Ratio of total shale rock fragments relative to total quartz for all facies 98 1 INTRODUCTION The Price Formation consists of interbedded shale, siltstone and sandstone and is exposed throughout much of West Virginia and southwest Virginia.